Introduction: Medication noncompliance has a significant effect on morbidity, mortality, and ease of living in diabetic patients. Non-compliance may be associated with patient demographics, the complexity of the drug regimen, dosage frequency, adverse effects, or some combination of these. Aim: To study the prevalence of treatment non-compliance among elderly diabetic patients in Majmaah, KSA. Method: A cross-sectional questionnaire-based study among elderly patients registered with the primary health center in Majmaah, Saudi Arabia. Results: Patients with a neutral attitude towards the disease and some knowledge of diabetes were more likely to be non – compliant with their treatment than those who do not have any knowledge of diabetes or with a positive/negative attitude. Conclusion: A high prevalence of non – compliance is still a problem in the treatment of elderly diabetic patients, particularly those who had positive risk factors. Further studies are needed to reduce noncompliance through various ways and means.